Rotary drive and joint breakout mechanism

ABSTRACT

A rotary table drive for a blasthole drill has a pair of roller elements pivotally mounted in a table bushing and engageable with cooperative longitudinal flat sided recesses formed on the exterior of a heavy walled cylindrical drill pipe to form the rotary drive connection with the drill stem. Multiple sections of the drill pipe may be used to make up a drill stem. A pulldown traverse frame mounted for longitudinal movement along the rig mast includes a rotary coupling member connected to the top end of a drill pipe section. The traverse frame also includes a drive transfer mechanism which is engageable with the rotary table for transferring the rotary drive effort from the table through the coupling member to the drill stem when the top end of a drill pipe section is passed downward through the table bushing. The drive transfer mechanism can be nonrotatably locked to provide for breakout of the threaded joint between a drill pipe section and the coupling member. A deck mounted wrench for engaging a toothed flange on the rotary table together with a power operated holding wrench is also used to breakout drill stem connections.

[ Apr. 1,1975

ABSTRACT bushing A rotary table drive for a blasthole drill has a pairof roller elements pivotally mounted in a table and engageable withcooperative longitudinal flat sided recesses formed on the exterior of aheavy walled cylindrical drill pipe to form the rotary dri connectionwith the drill stem. Multiple sections of the drill pipe may be used tomake up a drill stem. A pulldown traverse frame mounted for longitudinalmovement along the rig mast includes a rotary coupling member connectedto the top end of a drill pipe section. The traverse frame also includesa drive transfer mechanism which is engageable with the rotary table fortransferring the rotary drive effort from the table through the couplingmember to the drill stem when the top end of a drill pipe section ispassed downward through the table bushing. The: drive transfer mechanismcan be nonrotatably locked to provide for breakout of the threaded jointbetween a drill pipe section MECHANISM [75] Inventors: Robert W. Hisey,Richardson; Larry E. Halwas, Garland, both of Tex.

Assignee: Gardner-Denver Company, Quincy,

July 16, 1973 Appl. No.: 379,664

64/235, 173/163, 175/195 Int. Fl6d 3/06 64/235, 23.6, 23.7, 23 R;175/195; 173/163 References Cited UNITED STATES PATENTS United StatesPatent Hisey et al.

[ 1 ROTARY DRIVE AND JOINT BREAKOUT [22] Filed:

[58] Field of Search.........

FMENTED APR 7 1915 sum 7 or a PATENTEDAPR Mars 2314.196

SHEET 8 BF 8 ROTARY DRIVE AND JOINT BREAKOUT MECHANISM BACKGROUND OF THEINVENTION Rotary table drives for earth drilling rigs hold certainadvantages over so-called top drive arrangements in that the weight ofthe rotary drive mechanism is not required to be supported by the drillrig mast or derrick and the reaction torque from the drill stem rotativeeffort can be transferred directly to the main frame of the drill riginstead of being imposed on the mast structure. These advantagessimplify the structural requirements of the mast itself. Additionally,the power transmission system is more compact and easily arranged for arotary table drive and often a portable drill rig may require a total ofonly one or two drive motors for propelling the rig, pulldown andhoisting of the drill stem, and rotation of the drill stem.

A longstanding problem in the use of rotary table drives for large earthdrilling rigs for drilling blastholes and other relatively shallow holesin hard rock is that the use of a conventional noncylindrical crosssection drill pipe or kelly for transmitting rotary motion from thetable to the drill stem does not provide a suitable annular area in thedrill hole for effective removal of the drill cuttings by the holecleaning fluid. ln order to provide suitable annular areas for drillcutting removal a flat sided drive member is required to be so largethat the corners formed by the intersections of the sides of the memberare disposed closely adjacent the side wall of the drill hole and aresubject to severe wear from unavoidable rubbing against the side wall.Additional severe wear which tends also to round of the corners and theflat sides of a conventional drive member is caused by abrasion from theconstant stream of drill cuttings passing upward during drilling aroundthe exterior of the drill stem portion which is in the hole. In a shorttime an unsuitable driving connection is formed between the socket orcomplementary opening in the rotary table and the drive member due towear which changes the cross sectional shape of the drive member itself.

Furthermore, if a square cross section or otherwise special rotary drivemember or kelly is used together with cylindrical cross section drillpipe, then the process of adding and removing drill stem sections issomewhat more complex and time consuming. Since the drive member orkelly is the only drill stem member which can be driven by therotarytable the kelly itself must be disconnected from the drill stem and setaside in the mast or placed down an auxiliary hole while additionaldrill pipe sections are added to or removed from the drill stem and thenthe kelly must be reconnected to the drill stem and reinserted in therotary drive bushing when rotation of the stem is desired. Conversely,if the drive member or kelly is retained in connection with the hoistingmechanism and over the drill hole centerline, then the mast height mustbe sufficiently great to hoist the length of the kelly and at least onesection of drill pipe up out of the table.

Accordingly, it is desirable to provide a rotary table drive for earthdrill rigs in combination with a drill stern which will provide for useof the drill pipe members making up the drill stem to be used as drivemembers engaged with the table drive itself. Such drill stem members arealso desirably of a configuration which will provide an annular area inthe drill hole between the drill pipe exterior and the side wall of thehole which will be of the proper size: to permit effective drill cuttingremoval from the bottom of the hole without using unnecessarily largequantities of hole cleaning fluid. It is further desirable in largerotary blasthole drills to be able to use relatively thick walledcylindrical drill pipe which can be driven directly by a rotary drivemechanism because such pipe configurations are capable of withstandinglarge axial pulldown forces without being susceptible to bending orkinking.

. SUMMARY OF THE INVENTION The present invention provides an improvedrotary drive arrangement for an earth drilling rig wherein a novelrotary table drive mechanism is used in combination with novel drillpipe or stem components which are adapted to be driven directly by therotary table without the use ofa special drill stern drive section. Therotary table drive mechanism of the present invention provides fordriving a drill stem made up of one or more substantially cylindricaldrill pipe sections adapted to engage driving members mounted in therotary table. The rotary table drive mechanism of the present inventionalso includes drill stem driving members which provide positive and lowfriction driving engagement with the drill stem and are mounted in sucha way that they are drivingly engageable with each drill pipe sectionwhich is added to the drill stem as the drill pipe sections pass throughthe rotary table. With the rotary table drive arrangement of the presentinvention cylindrical cross section or tubular drill pipe in a modifiedform is advantageously used as sectional drill stem members which aredirectly driven by an improved rotary table drive mechanism wherein wearon the pipe itself does not have harmful effects on the drive connectionwith the rotary table.

The present invention also provides a rotary drive transfer mechanismfor use with a rotary table drive in an earth drilling rig whereinsectional drill stem members may be rotatably driven while the endportions thereof are passed through the rotary table. The rotary drivetransfer mechanism of the present invention is particularly advantageousfor use with a rotary table drive which includes members engageable withcooperating drive surfaces on a drill stem member and wherein positivedriving engagement between the table and the drill stem member cannot beprovided when an end portion of a drill stem member is passed throughthe table during drilling operations.

The rotary drive transfer mechanism of the present invention alsoincludes means for nonrotatably locking a rotary coupling between adrill stem and a pulldown traverse frame whereby the drill stem membersmay be easily disconnected from the traverse frame.

The present invention further includes improved means for breaking outthreadled joints between sectional drill stem members and between adrill stem member and a drill bit portion. The joint breakout means ofthe present invention includes a power operated wrench for holding adrill stem member during breakout operations and which also provides forhandling the detachable drill bit portion in a fast and work savingmanner.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sideelevation of an earth drilling rig including the rotary drive and jointbreakout mechanisms of the present invention;

FIG. 2 is a front elevation of the drill rig of FIG. 1;

FIG. 3 is a plan view of the rotary table of the present invention takenfrom line 33 of FIG. 2;

FIG. 4 is a view from line 4-4 of FIG. 3; FIG. 5 is a section view takenalong line 5-5 of FIG.

FIG. 6 is a sectional elevation of the rotary table and drive bushing;

FIG. 7 is a longitudinal view of a section of drill pipe in accordancewith the present invention;

FIG. 8 is a section view taken along line 8-8 of FIG.

FIG. 9 is a section view taken along line 99 of FIG.

FIG. 10 is a plan view of the rotary drive bushing of the presentinvention;

FIG. 11 is an elevation view of the rotary drive bushing shown in FIG.10.

FIG. 12 is a plan view of a power operated holding wrench and bithandling tool;

FIG. 13 is a side elevation of the power operated holding wrench and bithandling tool of FIG. 12;

FIG. 14 is a view of a pair of removable shoes for use with the poweroperated holding wrench of FIGS. 12 and 13;

FIGS. 15 through 18 are views of the rotary drive transfer and breakoutmechanism showing the operation thereof;

FIG. 19 is a section view taken along line 1919 of FIG. 15; and,

FIG. 20 is a section view taken along line 20-20 of FIG. 18.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The rotary table drive andjoint breakout mechanism of the present invention is particularlysuitable for use with relatively large rotary blasthole drills which aredesigned for drilling holes to a maximum depth usually in the range of100 to 150 feet. Such types of drills are characterized by mechanism forexerting a heavy axial down thrust or pulldown force on the drill stemand bit portion while the drill stem including the bit is rotated toprovide for localized crushing and grinding of the rock and earth toform the drill hole. However, since the mode of drilling is generallysimilar to that practiced with other types of drilling rigs such as oiland water well drilling equipment it is contemplated that the presentinvention could be utilized with these as well as other rotary drillingdevices.

Referring to FIGS. 1 and 2 a portable rotary blasthole drilling rig isillustrated and generally designated by the numeral 22. The drill rig 22is characterized by a frame 24 which is mounted on spaced apart crawlers26. The frame 24 supports an elongated mast 28 which is mounted onsupport means 30 for pivotal movement between the erect or workingposition shown and a substantially horizontal position when the rig isbeing propelled from one drilling site to another. The mast 28 includestwo spaced apart longitudinal posts 32 on which are formed gear racks34. The mast 28 is adapted to support a longitudinal traverse frame 36which includes a pair of spaced apart rotatable shafts 38 and 40 eachhaving pinions 42 mounted thereon and engaged with the racks 34.Suitable flexible drive means such as endless chains designated bynumeral 44 are supported by the mast 28. The drive chains are suitablyengaged with the shafts 38 and 40 for rotating the shafts to advance thetraverse frame reversibly along the mast.

The traverse frame 36 includes a transverse yoke member 46 includingmeans for rotatably supporting a coupling member 48 for connecting thetraverse frame to a drill stem generally designated by numeral 50 andmade up of one or more elongated drill pipe sections 52. The drill stem50 also includes a stabilizing sub 54 and a rotary bit 56 connected tothe lower end thereof for forming a drill hole 58. The traverse frame 36is reversibly driven along the mast 28 by the chains 44 to exert anaxial feed or pulldown force on the drill stem 50 and to hoist the drillstem components out of the drill hole. A drive motor and transmissionunit 60 mounted on the rig 22 is connected by drive means 62 to theendless flexible chains 44 for driving the traverse frame 36 along themast. A more detailed description of the pulldown traverse frame 36 andits associated drive means is disclosed in US. Pat. application Ser. No.362,576 filed May 21, 1973.

In many applications of the rig 22 a single traversal of the frame 36down the mast will be sufficient to cause the formation of a drill holeof desired depth. However, when it is desired to form a hole depthgreater than that provided for by one pass of the frame 36, additionaldrill pipe sections must be added to the drill stem. Accordingly, thedrill rig 22 is provided with a storage rack 64 for holding a seconddrill pipe section 52. The storage rack may take various forms and maybe adapted to hold a plurality of drill pipe sections. The

rack 64 is exemplary and is of the type which is mounted in the mast 28on pivotal linkage members 66 and 68 adjacent the top and bottom of therack, respectively. A pressure fluid operated cylinder and piston device70 is connected to the member 68 for moving the rack 64 from theretracted position shown in FIG. 1 into a position whereby the pipesection 52 held by the rack is in line with the longitudinal axis of thedrill stem 50.

Referring to FIGS. 1 through 3 and FIG. 6 the drill rig 22 ischaracterized by a rotary table drive mechanism for imparting rotarymotion to the drill stem 50. The rotary table drive mechanism of thepresent invention is generally designated by numeral 72 and includes aboxlike housing 74 mounted on the frame 24. The housing 74 includesbearings 76 and 78 mounted therein for supporting a rotating tablemember 80. The table member 80 is characterized by a circular flange 82having radially projecting teeth 84 formed on the periphery thereof. Anaxial opening 86 through the table member 80 includes a square or flatsided portion 88 which forms a socket for receiving a removable rotarydrive bushing 90. The table member 80 also includes a bevel gear 92fixed on the underside of the flange 82 and engaged with a bevel pinion94 rotatably mounted in the housing 74. The pinion 94 is connected to ashaft 96 which in turn is drivenly connected to the drive motor andtransmission 60. The table housing 74 is mounted on the frame 24 so thatthe table member 80 extends slightly above the deck or platform 98,FIG. 1. A hinged cover 100 is shown in FIG. 3 for partially covering thetable member 80 in the vicinity where drill operating personnel normallywork when making up and breaking out threaded connections between thebit. stabilizing sub, and drill pipe sections.

The rotary table drive of the present invention includes the improveddrive bushing 90 which in combination with the drill pipe sections 52shown in FIGS. 7 through 9 provides for use of sectional drill stemmembers as the rotary driven member or what is sometimes referred to asthe kelly. Referring to FIGS. 6 through 11, the rotary drive bushing 90is characterized by a flat sided and square depending portion 101 whichis removably fittable in the complementary socket portion 88 in thetable 80. A circular flange 102 formed on the bushing includes aplurality of circumferentially spaced teeth 104 which project axiallyupwardly when the bushing is fitted in the table. The bushing 90 alsoincludes a central opening 106 through which the drill pipe sections 52pass during drilling and hoisting opera tions. Recesses 108 are formedin two opposed sides of the portion 101 and intersect the opening 106.The recesses 108 are formed to accommodate a pair of drive rollers 110which are mounted to be substantially par allel to each other and toproject partially into the opening 106. The rollers 110 are eachrotatably mounted on a support plate 112 having a hub portion 114 formounting the rollers to swing about a substantially vertical pivotformed by pins 116 projecting through the hub portion of each supportplate. The pins 116 are suitably retained on the bushing 90. The hubportions of the support plates 112 each include a recess 118 in which ispositioned a torsion coil spring 120 surrounding the pin 116 and engagedwith the support plate for biasing the roller 110 inwardly toward thecenter of the opening 106. The support plates 112 also includeprojecting tabs 122, as shown in FIGS. and 11, which engage projections124 formed on the bushing 90 so as to limit the inward swinging movementof the rollers toward the center of the opening 106. The bushing 90 alsoincludes a pair of recesses 126 located adjacent to the opening 106 andopposed to each other along a line through the center of the opening asshown in FIGS. 6 and 10. The recesses 126 have disposed thereinpivotally mounted dogs 128 which may be pivoted to project into theopening 106 for engaging holding slots formed in a drill stem membersuch as the pair of slots 130 in the stabilizer 54 as shown in FIG. 6.When not required for holding a drill stem member the dogs 128 may beswung away from the opening 106 to lie along the sloped surfaces of therecesses 126.

Referring to FIGS. 7 through 9 a drill pipe section 52 is illustratedwhich is adapted to be used as the member rotatably driven by the rotarytable bushing 90 and which may be used as part of the drill stemdisposed in the drill hole without suffering wear which would be harmfulto the driven surface portions engaged with the rollers 110. The drillpipe section 52 is basically a cylindrical thick walled steel tubehaving a central longitudi nal passage 131 for conducting hole cleaningfluid through the drill stem to the bottom of the drill hole. The drillpipe section 52 includes an externally threaded portion or pin 132 atone end and an internally threaded portion 134 or box at the oppositeend. The threaded portions 132 and 134 will be assumed to be of the"right hand" for purposes of this disclosure. A slightly reduceddiameter portion 136 is formed at the pin end of the section 52. Thedrill pipe section 52 also includes a pair of longitudinal recesses 138formed in the outer cylindrical wall surface 139. The recesses 138extend over a major portion of the drill pipe section 52 and includeparallel and opposed surface portions 140. The surfaces 140 are eachintersected by a surface 142, which intersection is such that thesurfaces 140 and 142 of each groove 138 are substantially perpendicularto each other. The surfaces 142 are formed to be coplanar and lie in alongitudinal plane which passes through the longitudinal rotational axis143 of the drill pipe section 52.

As shown in FIG. 10 the surfaces 142 of the grooves 138 are disposed tobe engaged by the rollers 110 whereby rotation of the bushing willimpart rotation to the drill pipe section 52. As may be seen in FIG. 10the drive faces 144 of the rollers are provided with a taper or slopewith respect to the axis of rotation of the rollers which provides forclearance along the surface 140 of the grooves 138 with respect to thesides of the rollers when the rollers are drivingly engaged with thesurfaces 142. As may be noted also from FIG. 10 the location of thepivot pins 116 for the roller support plates are radially further fromthe rotational axis of the drill pipe section'52 than the drive surfaces142 which engage the rollers and are positioned such that when therollers are driving the drill stem rotatably a force couple is formedabout the pivot pins 116 which tends to swing the rollers inwardlytoward the center of the opening 106 to assure maximum engagement of thesurfaces 142 with the roller drive faces 144. With the arrangement ofthe rollers 110 and drive surfaces 142 as provided on the drill pipesection 52 the drill pipe can be easily proportioned to be of the propersize to provide the desired annular area in the drill hole for effectivedrill cuttings removal and furthermore the drive surfaces 142 are notaffected by rubbing of the drill pipe against the side wall of the holeor by abrasion from the drill cuttings passing upward out of the holearound the drill stem. Moreover. by providing the drill pipe section 52with surfaces 142 which are substantially flat and radially extendedwith respect to the longitudinal axis of the pipe section the directionof the driving force transmitted from the rollers 110 to the drill pipesection 52 is more effective for turning the drill stem 50. Accordingly,a more positive and long lasting drive connection may be maintained withthe rotary device disclosed herein.

The drill pipe section 52 also includes a pair of slots or recesses 148in the outer wall surface near the pin end which recesses are forengagement with the dogs 128 in the rotary bushing for holding the drillpipe section in the bushing during joint makeup and breakout operations.The drill pipe section 52 also is characterized by a pair of opposedgrooves 150 disposed near the lower end which are .cooperable with apair of jaws of a holding wrench to be described herein. If multiplepass drilling is performed by the drill rig 22 all of the drill pipesections may be of the same configuration as the section 52 shown inFIGS. 7 through 9. As shown in FIG. 7 and FIGS. 15 through 18 thegrooves 138 are formed such that the surfaces are sloped radiallyoutwardly with respect to the longitudinal axis of the drill pipesection toward the outside wall surface at the reduced diameter portion136. This flaring out of the grooves 138 provides for the rollers 110 tobe urged to swing outwardly away from the center of the opening 106 asthe end portion of the drill pipe section 52 passes down through theopening whereby the lower end of the next drill pipe section added tothe drill string may be initially passed into the opening 106 regardlessof any longitudinal misalignment of the drive surfaces 142 on one drillpipe section with the corresponding surfaces on the adjacent drill pipesection. When the pipe sections are being removed from the drill holethe table 80 may be rotated in the reverse or nondriving directionslightly to cause the rollers 110 to swing outwardly with respect to theopening l06so as not to engage or catch on the transverse end faces ofthe pipe sections as they are withdrawn from the hole. If single passdrilling only is to be performed the grooves 138 may be formed to extendentirely the length of the pipe section 52 to thereby provide drivingengagement of the rollers 110 throughout the entire length of thesection. With the drive transfer mechanism disclosed herein it isadvantageous to form the grooves 138 as shown in FIG. 7 since therollers are not drivingly engaged with the drill pipe at the end portion136 anyway.

For drilling operations wherein more than one section of drill pipe isto be used to increase the length of the drill stem for drilling deeperholes a drive transfer mechanism may be advantageously used with therotary table drive mechanism of the present invention so that thegrooves 138 of one drill pipe section 52 are not required to belongitudinally aligned with the corresponding grooves on an adjacentdrill pipe section in the drill stem. Referring to FIGS. 1, 2 andthrough the rotary drive transfer mechanism of the present inventionincludes the rotary coupling member 48 which is rotatably supported inbearings 152 and 154 mounted in a housing 156 on the yoke 46. The member48 includes an internal passage 158 in communication with a drill holecleansing fluid conduit 160. The lower end of the member 48 ischaracterized by an internally threaded portion 162 for receiving thepin end 132 of a drill pipe section 52. The member 48 also includes aplurality of longitudinal keyways 164 in which are slidably fitted keys166. The drive transfer mechanism further comprises a coupling sleeve168 having complementary grooves 170, FIG. 18, in which the keys 166 aredisposed to form a rotary driving connection between the sleeve and themember 48. The sleeve 168 includes a flange 172 at one end having a ringof circumferentially spaced and axially projecting teeth 174 which areengageable with complementary teeth 176 formed on a collar 178 fixed tothe yoke 46. The lower end of the sleeve 168 also includescircumferentially spaced teeth 180 which project axially downwardly andare voperable to be interfitted with the teeth 104 on the bushing 90 toform a driving connection between the bushing and the sleeve. The sleeve168 also includes a flange 182 which has disposed on its circumference aplurality of rollers 184. The rollers 184 are disposed in a radiallyinward facing channel 186 formed on a circular plate 188. The plate 188is attached to the ends of a pair of pressure fluid cylinder and pistontype actua tors 190. The cylinders 190 are slidably guided in tubularsleeves 192 disposed on the yoke 46. The distal ends of the cylinderpiston rods 194 are suitably fixed to the yoke 46 shown in FIG. 15.

The drive transfer mechanism also includes a second sleeve member 196disposed in a bore 197 in the sleeve 168 and adapted to surround andfrictionally grip the reduced diameter portion 136 ofa drill pipesection 52 as shown in FIGS. 15 and 16. The sleeve 196 includes keyways198, FIG. 19, in which are disposed the keys 166 to form a drivingconnection with the member 48.

As shown in FIG. 20 the sleeve 196 includes a plurality of slots 200which extend longitudinally a portion of the length of the sleeve alongwhich portion the exterior surface 202 of the sleeve is also sloped andis engageable with a correspondingly sloped collar 204 as shown in FIGS.15 through 18. The collar 204 is suitably retained in the interior ofthe sleeve 168 and is engageable with an inwardly projecting shoulderportion 206. The sleeve 196 also includes a shoulder portion 208engageable with the shoulder portion 206 on sleeve 168, as shown inFIGS. 17 and 18. The drive transfer mechanism provides for rotatablydriving the drill stem when an end portion ofa drill pipe section 52 ispassed through the rotary bushing so that sufficient hole depth isachieved to permit the addition of a drill pipe section to the drillstem and engagement of the rollers with the groves 138 of the sectionadded to the drill stem at the onset of drilling after the section hasbeen added. The drive transfer mechanism also is adapted to be used tobreak out the threaded connection between the member 48 and a drill pipesection.

An operating sequence of the drill transfer mechanism will now bedescribed in connection with viewing FIGS. 15 through 18. Duringdrilling operation, with the rotary drive being imposed on the drillstem 50 by the driving connection between the rollers 110 and a drillpipe section 52, the cylinders 190 are extended as shown in FIG. 15 tocause the collar 204 to compress the sleeve 196 to grip the reduceddiameter portion 136 ofa drill pipe section. This prevents theright-hand thread connection between the member 48 and the drill pipesection 52 from breaking loose due to the rotary driving effort imposedon the drill string which is in the direction of the arrow 210 in FIG.10.

As the pulldown traverse frame 36 feeds the drill stem downwardly to theposition shown in FIG. 16, the complementary teeth and 104 on the sleeve168 and bushing 90 become engaged and rotary driving effort istransferred from the bushing 90 to the coupling member 48 by way of thesleeve 168. Accordingly, rotation of the drill stem 50 is now no longerdependent on the rollers 110 driving against the surfaces 142 on thedrill pipe section. Continued axial down thrust by the traverse framewill result in axial sliding movement of the member 48 downward, viewingFIGS. 16 and 17, with respect to the sleeve 168 which will also causethe sleeve 196 to move downward with respect to the collar 204. Thesleeve 196 will, upon moving free of the radial inward wedging action ofthe collar 204, release its grip on the portion 136 of the drill pipesection 52, as shown in FIG. 17. The rotary drive now being from themember 48 to the drill pipe section 52 will, of course, tend to tightena right-hand threaded connection therebetween. The cylinders will beallowed to telescope into the sleeves 192 as the traverse frame 36 movesdownward from the FIG. 16 position to the FIG. 17 po' sition. As shownin FIG. 17 the top end of a drill pipe section 52 is now below therollers 110 and a drill pipe section to be added to the drill stem couldbe lowered into the opening 106 so that the rollers could engage thedrive surfaces 142. Prior to adding a drill pipe sec tion the threadedconnection between the member 48 and the upper end of a drill pipesection 52 must be broken out. To accomplish this the traverse frame 36is reversed to hoist the drill pipe section 52 up through the bushing 90until the dogs 128 can be pivoted into position in the recesses 148 tohold the drill pipe section in the position shown in FIG. 18 and in thesame manner as shown for the stabilizer 54 in FIG. 6. The cylinders 190are then actuated to move the sleeve 168 upward until the teeth 174 areinterfittingly engaged with the teeth 176 as shown in FIG. 18 wherebythe sleeve 168 and member 48 are nonrotatably locked. The rotary table80 is then driven in the direction of the arrow 210 of FIG. to rotatethe pipe section 52 with the rollers 110 as well as the dogs 128drivingly engaged in their respective recesses until the pipe section 52is disconnected from the member 48. After moving the traverse frame 36up the mast 28 an additional drill pipe section 52 can be added bypositioning a suitable storage rack such as the rack 64 over the axis ofthe drill stem and rotating the table 80 in reverse to make up athreaded connection between the drill pipe section supported in thetable and the section being added. The traverse frame 36 is then loweredto engage the coupling member 48 with the section added to the drillstem whereby further reverse rotation of the table would thread the pinend 132 ofa drill pipe section into the threaded portion 162 on thecoupling member. The cylinders 190 are extended after the couplingmember is reconnected to the drill string to unlock the sleeve 168 andto cause the sleeve 196 to be lowered into frictional grippingengagement with the top portion of the drill pipe section now connectedto the coupling member 48.

If a drill pipe section is to be removed from the drill stem 50 thethreaded connection between a drill pipe section 52 and the couplingmember 48 would be broken loose generally in accordance with the abovedescribed procedure. Then, prior to complete separation of the couplingmember 48 from the drill pipe section, the traverse frame 36 is raisedup the mast to pull the pipe section to be removed from the drill stemup through the table bushing 90 until the upper portion of the drillpipe section which is below the one to be removed is in position to havethe recesses 148 engaged by the dogs 128 and the recesses 138 engaged bythe rollers 110. With the drill pipe storage rack in position to receivethe pipe section being removed from the drill stem or an auxiliaryhoisting line connected thereto, the table 80 is rotated forward, thedirection of arrow 210 in FIG. 10, until the coupling member 48 isseparated from the pipe section being removed. Then a suitable holdingwrench such as the wrench described hereinbelow is engaged with thegrooves 150 of the pipe section being removed from the drill stringwhile the table 80 again is rotated forwardly to break out the jointbetween the section being removed and the section supported in the tablebushing 90.

The rotary drive and joint breakout mechanism of the present inventionincludes improved auxiliary breakout and drill stem component handlingdevices.

Referring to FIGS. 3 through 5 a rotary table turning arm 230 issupported for sliding movement in the frame 224 and includes a hook 234formed on the end which is opposite the end connected to the piston rod228. The frame 224 is suitably connected to a pressure fluid actuator236 by way of a member 238 whereby in response to operation of theactuator the device 220 may be pivoted into the position shown in FIG. 3and held for engagement of the hook 234 with one of the radiallyprojecting teeth 84 on the table 80. The actuator 236 is mounted onbracket 240 which is disposed on the deck 98 and which also partiallysupports the frame 224. With the hook 234 positioned to engage a toothon the table the cylinder 226 may be actuated to retract the piston rod228 so as to rotate the table 80 with great force a small portion of a.revolution for breaking out drill string connections which cannot beloosened with the turning effort available from the motor andtransmission 60 through the table drive gears 92 and 94. When thebreakout device 220 is not in use the actuator 236 is energized to pivotthe frame 224 so that the hook 234 is moved radially away from the table80.

Referring to FIG. 3 and FIGS. 12 through 14 the drill rig 22 includes adrill stem holding wrench 250 which is also adapted to handle a drillbit for adding and removing the same with respect to the drill stem 50.The wrench 250 includes a power rotated base 252 having a shaft portion254 rotatably mounted in a bearing sleeve 256 supported on the rigsubstantially below the deck 98. The base 252 includes a sprocket 258fixed thereon and engaged with a chain 260 which is drivenly connectedto a sprocket 262 mounted on the shaft of a suitable drive motor, notshown. The base 252 includes an upstanding part 264 upon which a boom266 is mounted for movement about a horizontal pivot 268. A hydrauliccylinder 270 is connected between the boom 266 and the part 264 forraising and lowering the boom about the pivot 268. The boom 266 isadapted to receive a partially tubular member 272 which is securedagainst rotation with respect to the boom by a pair of removable pins274. The member 272 includes a portion formed in part by two spacedapart plates 276. A pair of holding jaws 278 and 280 are mounted betweenand supported for pivotal movement with respect to the plates 276. Eachjaw includes a short arm portion 282 which is connected by means of alink 284 to a clevis 286. The clevis 286 is connected to a piston rodportion of a linear pressure fluid actuator 288 mounted on the member272 for moving the jaws between the closed position shown by the solidlines in FIG. 12 and the open position shown by the dashed lines. Theholding jaws 278 and 280 have removable shoes 290 secured on the jaws bypins 294. The jaws 278 and 280 each also includes a depending member 296having a projection 298 formed on the lower end thereof, viewing FIG.13, which is engageable with a bail 300 mounted on a bit holding fixture302.

The bit holding fixture 302 is characterized by a cylindrical portion304 which is adapted to be retained in suitable receptacles 306, oneshown in FIG. 3, in the deck of the rig 22. A flat sided flange 308 isattached to the portion 304 and is adapted to fit in the socket oropening 88 of the table 80 in place of the bushing 90. The flange 308also has a socket opening 310 formed to closely fit around the integrallegs of a roller type rotary bit such as the bit 56 in FIGS. 1 and 2,whereby with the fixture disposed in the table 80 and surrounding thebit the table may be rotated to make up or break out a connectionbetween the bit and the stabilizer 54.

The process of changing bits on the drill rig 22 may be performed byraising the traverse frame 36 and drill stem up the mast 28 until thelower end of the bit 56 is pulled up through the table 80 and above decklevel sufficiently to permit swinging the holding wrench 250 from aretracted position, as shown in FIG. 3, with a fixture 302 attachedthereto into position over the table. The fixture 302 is then loweredinto the opening by operation of the cylinder 270 and the jaws 278 and280 are at least partially closed to disconnect the members 296 from thebails 300. When the drill string is removed from the hole the flutes 55,see FIG. 6, on the stabilizer 54 engage the bushing 90 and carry itupwardly out of the table 80 to provide for accommodation of the fixture302 in the table opening 88. After placement of the fixture 302 in thetable 80 the bit 56 is lowered into the socket 310 and the jaws 278 and280 with modified shoes 314, as shown in FIG. 14, disposed thereon areclosed so that projections 316 on the shoes 314 are engaged with thesides of grooves 57 in the stabilizer. The table 80 is then rotated,while the stabilizer 54 is prevented from rotation, to break a threadedconnection between the bit and stabilizer. The bit fixture 302 with abit disposed therein may then be removed from the table by the wrench250 and deposited in a receptacle 306, and a similar fixture and bit canthen be picked up and swung into place in the table opening. With thenew bit disposed in the table the drill stem and stabilizer are loweredand the table rotated in reverse to make up a joint between the bit andstabilizer. The wrench 250 may be used to hold the stabilizernonrotatably while the joint is being made up. The drill stem includingthe new bit is then raised to remove the bit from the fixture 302 andafter retraction of the wrench 250 and fixture to the stored positionthe drill stem is lowered into the table and the bushing 90 returnedinto the opening 88 preparatory to a drilling operation.

The wrench 250 is also used to hold a drill pipe section 52 whilethreaded joints between sections are made up or broken loose. Byrotation of the base 252 and operation of the boom cylinder 270 thewrench may be moved when desired into a position with the jaws 278 and280 surrounding the drill stem 50. The

shoes 290 shown in FIG. 12 include surfaces 292 engageable with thesides of the grooves 150 for holding a drill pipe section 52 while thetable is rotated to break one section loose from another.

The wrench jaws 278 and 280 may also be inverted by removing the pins274, rotating the member 272 in the boom 266, and then reinserting thepins. This inversion of the jaws 278 and 280 may be performed so thatthe shoes 290 can be engaged with the surfaces 142 to hold one drillpipe section from rotating while the table 80 is rotated in reverse,with another drill pipe section or stabilizer 54 supported therein bythe dogs 128, to tighten a joint.

As may be appreciated from the foregoing description the presentinvention provides improved rotary drive means for rotating a drillstring in a rotary earth drilling rig. The rotary drive means of thepresent invention together with a novel drive transfer mechanism and theholding wrench and bit handling device 250 provides for more rapid andefficient drilling operations on rotary drill rigs than was heretoforeknown.

What is claimed is:

l. A rotary drive arrangement for rotating a drill stem on an earthdrilling rig comprising:

a member disposed for rotation on said drilling rig and including anopening in which said drill stem is disposed for longitudinal movementwith respect to said member;

said drill stem comprising at least one elongated drill pipe sectionhaving a pair of opposed recesses in the outer wall surface of saiddrill pipe section, each recess forming a drive surface extending inwardfrom the intersection of said recess with said outer wall surfacegenerally toward the longitudinal axis of said drill pipe section, saiddrive surfaces extending longitudinally over a major portion of thelength of said drill pipe section; and,

a pair of drive rollers engageable with said drive surfaces for rotatingsaid drill pipe section in response to the rotation of said member, saidrollers being disposed on support members which are mounted on pivotmeans on said member so that said rollers may be pivotally moved intoand out of engagement with said drive surfaces.

2. A rotary drive arrangement for rotating a drill stem on an earthdrilling rig comprising:

a member disposed for rotation on said drilling rig and including anopening in which said drill stem is disposed for longitudinal movementwith respect to said member;

said drill stem comprising at least one elongated drill pipe sectionhaving a pair of opposed recesses in the outer wall surface of saiddrill pipe section, each recess forming a drive surface extending inwardfrom the intersection of said recess with said outer wall surfacegenerally toward the longitudinal axis of said drill pipe section, saiddrive surfaces being parallel and coplanar and extending longitudinallyover a major portion of the length of said drill pipe section; and,

a pair of drive rollers engageable with said drive surfaces for rotatingsaid drill pipe section in response to the rotation of said member, saidrollers including drive surfaces which are tapered with respect to theaxis of rotation of said rollers and are engageable with the drivesurfaces of said drill pipe section in such a way that surface portionsof said recesses other than said drive surfaces are substantiallyprevented from engagement with said rollers when said rollers arerotatably driving said drill pipe section.

3. A rotary drive arrangement for rotating a drill stem on an earthdrilling rig comprising:

a member disposed for rotation on said drilling rig and including anopening in which said drill stem is disposed for longitudinal movementwith respect to said member;

said drill stern comprising at least one elongated drill pipe sectionhaving recesses in the outer wall surface thereof, each recess forming adrive surface extending inward from the intersection of said recess withsaid outer wall surface generally toward the longitudinal axis of saiddrill pipe section, said drive surfaces extending longitudinally over amajor portion of the length of said drill pipe section; and,

drive means engageable with said drive surfaces for rotating said drillpipe section in response to the rotation of said member, said drivemeans being disposed on support members which are mounted on pivot meanson said member so that said drive means may be pivotally moved into andout of engagement with said drive surfaces.

4. The invention set forth in claim 3 wherein:

said pivot means for mounting said support members on said member aredisposed on said member further from the longitudinal axis of said drillpipe section than the point of engagement of said drive means with saiddrive surfaces on said drill pipe section so that in response to saiddrive means forcibly engaging asid drill pipe section a force couple isformed which tends to pivot said drive means to ward said longitudinalaxis of said drill pipe section.

5. The invention set forth in claim 3 together with:

biasing means on said member engaged with said support members forbiasing said drive means into said opening in said member.

6. The invention set forth in claim 5 together with:

stop means on said support members for engaging cooperating stop meanson said member for limiting the pivotal movement of said drive meansinto said opening.

7. The invention set forth in claim 1 wherein:

said pivot means for mounting said support members on said member aredisposed on said member further from the longitudinal axis of said drillpipe section than the point of engagement of said rollers with saiddrive surfaces on said drill pipe section so that in response to saidrollers forcibly engaging said drill pipe section a force couple isformed which tends to pivot said rollers toward said longitudinal axisof said drill pipe section.

8. The invention set forth in claim 1 together with:

biasing means on said member engaged with said support members forbiasing said rollers into said opening in said member.

9. The invention set forth in claim 8 together with:

stop means on said support members for engaging cooperating stop meanson said member for limiting the pivotal movement of said rollers intosaid opening.

10. The invention set forth in claim 3 wherein:

said rotary drive arrangement comprises a rotary table having a housingsupporting a rotatable table member, and said member comprises a bushingremovably fitted on said table member to be rotatably driven by saidtable member.

1. A rotary drive arrangement for rotating a drill stem on an earthdrilling rig comprising: a member disposed for rotation on said drillingrig and including an opening in which said drill stem is disposed forlongitudinal movement with respect to said member; said drill stemcomprising at least one elongated drill pipe section having a pair ofopposed recesses in the outer wall surface of said drill pipe section,each recess forming a drive surface extending inward from theintersection of said recess with said outer wall surface generallytoward the longitudinal axis of said drill pipe section, said drivesurfaces extending longitudinally over a major portion of the length ofsaid drill pipe section; and, a pair of drive rollers engageable withsaid drive surfaces for rotating said drill pipe section in response tothe rotation of said member, said rollers being disposed on supportmembers which are mounted on pivot means on said member so that saidrollers may be pivotally moved into and out of engagement with saiddrive surfaces.
 2. A rotary drive arrangement for rotating a drill stemon an earth drilling rig comprising: a member disposed for rotation onsaid drilling rig and including an opening in which said drill stem isdisposed for longitudinal movement with respect to said member; saiddrill stem comprising at least one elongated drill pipe section having apair of opposed recesses in the outer wall surface of said drill pipesection, each recess forming a drive surface extending inward from theintersection of said recess with said outer wall surface generallytoward the longitudinal axis of said drill pipe section, said drivesurfaces being parallel and coplanar and extending longitudinally over amajor portion of the length of said drill pipe section; and, a pair ofdrive rollers engageable with said drive surfaces for rotating saiddrill pipe section in response to the rotation of said member, saidrollers including drive surfaces which are tapered with respect to theaxis of rotation of said rollers and are engageable with the drivesurfaces of said drill pipe section in such a way that surface portionsof said recesses other than said drive surfaces are substantiallyprevented from engagement with said rollers when said rollers arerotatably driving said drill pipe section.
 3. A rotary drive arrangementfor rotating a drill stem on an earth drilling rig comprising: a memberdisposed for rotation on said drilling rig and including an opening inwhich said drill stem is disposed for longitudinal movement with respectto said member; said drill stem comprising at least one elongated drillpipe section having recesses in the outer wall surface thereof, eachrecess forming a drive surface extending inward from the intersection ofsaid recess with said outer wall surface generally toward thelongitudinal axis of said drill pipe section, said drive surfacesextending longitudinally over a major portion of the length of saiddrill pipe section; and, drive means engageable with said drive surfacesfor rotating said drill pipe section in response to the rotation of saidmember, said drive means being disposed on support members which aremounted on pivot means on said member so that said drive means may bepivotally moved into and out of engagement with said drive surfaces. 4.The invention set forth in claim 3 wherein: said pivot means formounting said support members on said member are disposed on said memberfurther from the longitudinal axis of said drill pipe section than thepoint of engagement of said drive means with said drive surfaces on saiddrill pipe section so that in response to said drive means forciblyengaging asid drill pipe section a force couple is formed which tends topivot said drive means toward said longitudinal axis of said drill pipesection.
 5. The invention set forth in claim 3 together with: biasingmeans on said member engaged with said support members for biasing saiddrive means into said opening in said member.
 6. The invention set forthin claim 5 together with: stop means on said support members forengaging cooperating stop means on said member for limiting the pivotalmovement of said drive means into said opening.
 7. The invention setforth in claim 1 wherein: said pivot means for mounting said supportmembers on said member are disposed on said member further from thelongitudinal axis of said drill pipe section than the point ofengagement of said rollers with said drive surfaces on said drill pipesection so that in response to said rollers forcibly engaging said drillpipe section a force couple is formed which tends to pivot said rollerstoward said longitudinal axis of said drill pipe section.
 8. Theinvention set forth in claim 1 together with: biasing means on saidmember engaged with said support members for biasing said rollers intosaid opening in said member.
 9. The invention set forth in claim 8together with: stop means on said support members for engagingcooperating stop means on said member for limiting the pivotal movementof said rollers into said opening.
 10. The invention set forth in claim3 wherein: said rotary drive arrangement comprises a rotary table havinga housing supporting a rotatable table member, and said member comprisesa bushing removably fitted on said table member to be rotatably drivenby said table member.